Police investigate triple muder-suicide in Shaler Township, Pa.

(CBS/KDKA/AP) SHALER TOWNSHIP, Pa. - A father killed his wife and two young daughters before he shot himself inside their home in a suburb of Pittsburgh Sunday night, police said.

Police responded to the scene after initial reports of an argument and shots being fired. When police arrived they found four people inside with gunshot wounds to the head, reports CBS station KDKA.

"We have a young girl that's in the hallway leading back to the bedroom. We have a mother and an infant in the bed in the bedroom and the father in the bedroom in and around the closet area," Shaler Police Chief Jeff Gally said to the station.